1. Field of the Invention
The present invention relates to alarm technology and more particularly to a door lock alarm, which gives off an alarm signal if the door lock is not locked after closing of the door panel to the door frame.
2. Description of the Related Art
The door panel of the door of a house is normally equipped with a door lock. If users forget to lock the door after access, thieves can get into the house to steal things, or to endanger the personal safety of residents. An advanced electronic door lock has the function of giving off a warning signal if the door lock is not locked. However, it costs a lot to replace an existing conventional door lock with an advanced electronic door lock. Further, certain door panels are not suitable for mounting an advanced electronic door lock. Therefore, it is desirable to provide an alarm for use in a door panel being equipped with a conventional door lock, which can give off an alarm signal if the door lock is not locked after the door is closed.